<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    .box {
        width: 100px;
        height: 100px;
        background-color: pink;
    }
</style>
<body>
    <div class="box"></div>
    <script>
        let box = document.querySelector('.box')
        box.style.width = '10000px'
    </script>
</body>
</html>